This section is intended to provide a background or context to the invention recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Rock drills are typically used to penetrate rock or another surface (i.e., the drilling surface), often as part of a mining operation. These rock drills typically include a drill tool positioned on the end of a drill shank for cutting into the drilling surface. While drilling, the rock drill applies a percussive or oscillating force to the drill tool, driving the drill tool into the drilling surface. At the same time, the rock drill applies a rotative force to the drill shank and drill tool (i.e., sometimes as part of a drill string) in order to send flushing media to the drill tool, and/or to flush rock or other debris away from the drilling surface.
Typically, rock drills include a drill shank bearing or bushing in order to house the drill shank and constrain or control a movement of the drill shank as the drill shank rotates and/or oscillates. During the drilling operation, the drill shank and the drill shank bearing may be subjected to heavy wear due to rock, dirt, sand, water, and other materials flowing along the surface of the components. In addition, as the drill shank rotates and/or oscillates, the drill shank bearing may rotate or otherwise move within the rock drill, creating a friction with the rock drill components and causing further wear to the drill shank bearing. As a result, the drill shank bearing becomes worn relatively quickly and must be changed frequently, which leads to downtime for the rock drill.
Typical drill shank bearings have a rounded shape, similar to the shape of the drill shank. The rounded shape allows the drill shank bearing to move relative to the rock drill as the drill shank rotates and/or oscillates, resulting in further wear to the drill shank bearing and requiring more frequent replacement. Also, in order to replace a typical drill shank bearing, the rock drill must be substantially disassembled. The typical drill shank bearing is pressed into a relatively heavy housing cover, which must be removed and transported to a press in order to replace the drill shank bearing. In a typical replacement operation, the worn drill shank bearing with the rounded shape must be pressed out of the housing cover, a new drill shank bearing must be pressed back into the housing cover, and the housing cover must be transported back to the rock drill for re-assembly.